Assessment of the risk of pollution from Arsenic on human health as a function of its speciation in intestinal fluids

Volume:133 (2014) f.2 Pages:161-168 DOI:10.3301/IJG.2013.21

Abstract

AbstractInvestigating the risk on human health arising from exposure to As-polluted drinking water is a very important task since many area of the world has to face with this problem. Actually, chronic poisoning by arsenic carried by water has been well documented in many European and extra-European countries. Pollution of water with arsenic develops generalized symptoms of poisoning and carcinogenesis.
It is well known that inorganic As is rapidly absorbed after oral exposure, but little information is still available about the fate of arsenic after oral ingestion. In particular, the mechanism which affects the speciation of this element in the gastrointestinal tract is not clear, especially when other trace elements are present. In this paper we present an estimate of the health risk due to the ingestion of water containing micro-pollutants, such as As and B, using two
computational codes: PHREEQC, which allowed us to determine the effect of boron on arsenic speciation in equilibrium with the fluids of the gastrointestinal tract; SADA software for assessing the risk of exposure to contaminated matrices. The use of software in the present case study is mandatory since it is quite impossible to obtain experimental data. We focused on a sample area, the geothermal field of Larderello (Italy), where anomalous concentrations of arsenic and boron were found in the drinking water.
The results obtained in this study prove that the risk to human health depends on the speciation of As, which is strictly related to the pH values reached at equilibrium with intestinal fluids. The pH values change as a function of the concentration of boric acid in drinking water. In waters characterized by high contents of B, the risk factor is amplified by the increase of the species As3+ in intestinal fluids. Specifically, this study suggests that interactions between two elements in solution, such as boric acid and arsenic, both in solution in drinking water, can have a negative impact on human health when balanced with intestinal fluids, since the effects of one may magnify the toxicity of the other.

Using Tephrochronology and palynology to date the MIS 13 lacustrine sediments
of the Mercure basin (Southern Apennines - Italy)

Volume:133 (2014) f.2 Pages:169-186 DOI:10.3301/IJG.2013.22

Abstract

AbstractThe paper deals with the chronostratigraphy of the lacustrine infilling of the Mercure basin, an intramontane depression of the Southern Apennines, located along the Calabria-Lucania boundary.
A preliminary tephrochronologic investigation and pollen analyses were carried out on the infilling succession exposed along V-shaped tributary valleys of the Mercure river. Lithological and chemical features of the thickest and best preserved tephra layer were fully characterised, and single crystal 40Ar/39Ar dating was performed yielding an age of 514±16 ka. Pollen analyses revealed the occurrence of warm and humid interglacial conditions that were correlated to MIS 13 on the basis of the age determination. The chemical compositions of glasses indicate that the Sabatinian volcanic field is the most probable source of the investigated tephra layer. Although chemical features support a correlation with the Tufo Giallo della Via Tiberina multiphase eruption that occurred between 561 and 548 ka, the integration of tephrochronology and pollen analysis points to a younger age, falling within MIS 13. We propose a correlation with one of the four explosive events that occurred in the Latial district from 514 to 449 ka. The Mercure tephra layer, owing to its age and great distance from the presumed source, represents a valid correlating tool for MIS 13 in central-southern Italy.

Geoheritage and sport climbing activities: using the Montestrutto cliff (Austroalpine domain, Western Alps) as an example of scientific and educational representativeness

Volume:133 (2014) f.2 Pages:187-199 DOI:10.3301/IJG.2013.24

Abstract

AbstractNumerous sites of geological and geomorphological interest (i.e., geosites or geomorphosites) have been recently individuated around the Alps, testifying to the great geodiversity that characterises this mountain range. Some rock cliffs that have been locally equipped as sport climbing sites may also be considered as sites of geological and geomorphological interest: the combination of features such as educational exemplarity and geohistorical importance
increase the scientific value of these sites. Progression along climbing routes is intimately connected with the geological and geomorphological features of the cliff; thus, it may be possible to interest typical climbers in the area of the Earth Sciences.
A research study was conducted at the Montestrutto climbing wall (Western Alps, Italy), which is located in the Eclogitic Micaschist Complex of the Austroalpine Domain, with the following objectives: i) to reconstruct the deformation stages at local scales along the sport climbing wall and in the surroundings; ii) to analyse
how geological elements are related to the physical elements needed for vertical progression to strengthen the link among geology, morphology and the grade of the routes, and finally iii) to use previous results to evaluate the potential of Montestrutto as a geosite. The detailed study consisted of the quantitative analysis of five routes of varying degrees of difficulty, which produced an interesting relationship among the level of difficulty of the routes and the geological and geomorphological features of the sport climbing wall. The Montestrutto cliff is considered to be a valuable geosite because of the scientific importance (e.g., representativeness, educational exemplarity and geohistorical importance) associated with its high cultural and socio-economic value and high potential for use. Sport climbing in sites such as Montestrutto, which are both scientifically significant and accessible, also in terms of the level of climbing difficulty, could be considered as a possible vehicle for stimulating public interest in the Earth Sciences.

First report of Lutra simplicidens (Carnivora, Mustelidae, Lutrinae) in the Early Pleistocene of the Upper Valdarno (Italy)
and the origin of European otters

Volume:133 (2014) f.2 Pages:200-203 DOI:10.3301/IJG.2013.25

Abstract

AbstractFossil Lutrinae are very rare in the Plio-Pleistocene fossil record. We report here a right mandible of an otter from the Early Pleistocene of the Upper Valdarno Basin (Italy) kept in the collections of the Natural History Museum of London. The specimen, recovered in the XIX century, remained undescribed until today. Morphologic and morphometric characters of the mandible allow us to refer it to Lutra simplicidens THENIUS, 1965, a fossil otter recorded in Europe in the late Early to Middle Pleistocene, thus representing the oldest report of this species. This finding adds a new interesting taxon to the late Villafranchian faunal assemblage of the Upper Valdarno and reinforces the hypothesis of an African origin of L. simplicidens, because of its affinities with L. fatimazohrae GERAADS, 1997 from Morocco.

An analytical model for the geotherm in the Basilicata oil fields area (southern Italy)

Volume:133 (2014) f.2 Pages:204-213 DOI:10.3301/IJG.2014.02

Abstract

AbstractA geothermal model for the area of the Basilicata oil fields has been obtained by an analytical procedure. The model takes into account both the temperature variation due to the re-equilibrated conductive state after thrusting and frictional heating. Input parameters include heat flow density data and a series of geologically derived constraints – thrust depth, timing of thrusting, slip rate – obtained by the integration of surface and subsurface datasets. For the top 5 km of the crust, the resulting geothermal curve shows a remarkably good fit with temperatures recorded from deep oil wells.
The new geotherm provides a fundamental constraint for rheological and stress accumulation modelling in the seismically active study area. Furthermore, the analytical solution provided in this study may be used as a basis to calculate the relevant geotherm for further areas and/or tectonic settings.

The amount of pure shear and thinning in the Hercynian continental lower crust exposed in the Serre Massif (Calabria, southern Italy): an application of the vorticity analysis to quartz c-axis fabrics

Volume:133 (2014) f.2 Pages:214-222 DOI: 10.3301/IJG.2014.03

Abstract

AbstractNew petrographic and geologic data on the lower continental crust exposed in the Calabrian Arc are reported with the aim to shed some lights on the thinning episode occurred during the late stages of the Hercynian orogeny. Previous petrologic studies provide some constraints for the decompression mechanisms in different levels of the continental crust. However, an integral view of the exhumation mode, which took place during the Late Carboniferous, is still missing.
This paper used the method of vorticity analysis, which takes into account new quartz c-axis measurements and microstructural observations on high-grade metasediments to estimate the value of the vorticity number (Wm).
In addition, calculation of Wm allowed obtaining: i) the percentage of pure vs. simple shear and ii) the amount of thinning of the Hercynian continental lower crust exposed in Calabria.
The final scenario is derived where pure shear played a major role in the thinning of the lower crust, whose original thickness is estimated to be two and half times the present-day value. Comparing this result with the well-known petrologic data, it is concluded that the late-Hercynian thinning preferentially took place in the lower crust and, along with erosion, would be the main responsible for the present-day overall crustal thickness.

Architecture of the western margin of the North Adriatic foreland: the Schio-Vicenza fault system

Volume:133 (2014) f.2 Pages:223-234 DOI:10.3301/IJG.2014.04

Abstract

AbstractIn the Italian Southern Alps, the Lombardic and Venetian chains and related foreland are separated by the Lessini-Berici-Euganei foreland block, which is unaffected by the Neogene-Quaternary shortenings. However, the Veneto-Friuli alluvial plain to the east of this foreland block has been affected by a poly-phase evolution since the Mesozoic era and represents the foreland of three surrounding chains. The area was affected by several flexural cycles related to the diachronous build-up of the External Dinarides to the east (Late Cretaceous-Late Eocene), the Eastern Southern Alps to the north (Late Oligocene-Quaternary), and the Northern Apennines to the southwest (Middle Miocene-Quaternary). The last two chains are currently active, although at different rates. The western margin of the foreland is marked by the Schio-Vicenza fault, which divides the deformed foreland (Veneto-Friuli alluvial plain) from the undeformed foreland (Lessini and Berici Mountains and Euganei Hills). The aim of this work is to unravel the architecture and evolution of this boundary using 2D seismic sections and deep wells acquired by ENI for hydrocarbon exploration. Approximately 1,000 km of seismic lines were interpreted and 10 wells were used to calibrate the seismic interpretation. Seven seismic sections that are sub-orthogonal to the main faults were selected to obtain geological cross-sections through a depth conversion process. The collected data display a complex buried fault system (Schio-Vicenza fault system) that extends with a NW-SE trend from the foot of the Prealps to the Po Delta. In the cross sections, the movement of the fault shows a vertical component with down-throw of its eastern side (hanging wall block). Some faults display a Mesozoic extensional displacement in accordance with the Mesozoic basin and swell architecture of the area. In addition, the Pliocene throw increases from the southeast to the northwest.
Therefore, the Schio-Vicenza fault system can be interpreted as an inherited Mesozoic structure that reactivated during the Neogene shortening of the area. In particular, this fault system appears to have been mainly active during the Pliocene-Quaternary flexural cycle that is related to the Northern Apennines subduction, which is when the fault system accommodated a scissor movement between the Veneto-Friuli foreland and the Lessini-Berici-Euganei block.

AbstractA detailed chronological scheme based on 14C and U/Th datings of Upper Pleistocene slope and alluvial deposits in the Upper Esino River Basin (Marche, central Italy), containing archaeological remains, pollens and land molluscs, constrains the time-range deposition of cold climate slope-waste and coeval alluvial deposits between the Middle Pleniglacial and Late Glacial. Integrating molluscan analyses and stratigraphical data (sedimentary features, 14C and
U/Th datings) from an Upper Pleistocene stratigraphical section of fluvial gravelly and sandy-silty sediments near Matelica (Macerata) allowed a detailed palaeoenvironmental reconstruction. Well preserved land gastropod assemblages from nine levels, typical of cold/cool climate and variable humidity of stadials and interstadials showing prevalence of open and dry environment, were analysed by quantitative methods. Palaeocommunity dynamics through the section, due to alternate cool-cold climatic conditions, proved to be consistent with sedimentary features: braid plain channel gravelly sediments of stadials yielded poor-species assemblages of very dry exposed places (steppe-like), sandy-silty sediments of interstadials recorded diversified molluscan fauna with steppe-prairie species and taxa of more or less damp conditions, suggesting more humid environment.
Dominance or decrease in specimen number of one species and variation in species composition were strongly influenced by palaeoclimatic changes, highlighting detailed climatic and palaeoenvironmental variations through time.

The significance of Longobucco Unit (Calabria-Peloritani Arc) in the evolution of the Ionian and Alpine Oceans

Volume:133 (2014) f.2 Pages:249-270 DOI:10.3301/IJG.2014.07

Abstract

AbstractIn the geological literature the Longobucco Unit, as well as the whole Calabria-Peloritani Arc (CPA), was interpreted in opposite ways: 1) as part of the African-Adria Plate (thus belonging to Austroalpine Units) previously involved in the eo-Alpine deformation with an european vergence and then thrust southeastwards on the Apennine chain; 2) as parts of the European continental margin involved only in the Apenninic orogeny; 3) as part of a microplate between two branches of the Alpine ocean (Pennidic O. and Ligurian O). In this paper we contribute to the solution of this controversial problem with basin analysis on the Longobucco Mesozoic cover, taking into account the paleogeographic evolution of the West Mediterranean area during the Mesozoic.
1) At first, the sedimentary successions of the Longobucco Unit (Early Jurassic-Miocene) are re-examined. The peculiar occurrence of conglomerates with pebbles of Variscan basement from the Early Jurassic, the existence of carbonate ramps attached to an exposed continental area in the Hettangian-Sinemurian and the huge amount of silici-clastic grains in the entire Mesozoic succession witness for the deposition on a continental margin exposed to either erosion and synsedimentary tectonics.
2) The coeval successions of the Apennines (Adria Plate), southern Sicily (African Plate) and eastern Sardinia (European Plate) are compared to understand which exposed areas had to be the source for the terrigenous sediments. Our conclusion supports the hypothesis (already formulated by various authors) that from the oceanic opening of the Alpine Ocean (Middle Jurassic) the Longobucco Unit and the whole CPA were part of the European Plate.
3) The comparison between the nappes stack of CPA and that well known in the Western Alps confirms the idea that the CPA cannot be considered as Austroalpine Unit. In fact, despite the same occurrence of granulitic facies, the differences are remarkable: different dip of subduction plane, different vergence, different age of HP/LT metamorphism, different age of exhumation and even different Mesozoic cover. Therefore CPA has to be considered as part of the European Plate.
4) The original position of CPA is very important to define the relationship between the Ionian and the Alpine Oceans in the western Mediterranean area. Here, the oceanic spreading of Ionian basin occurred in the Ladinian and, from the Late Eocene, this ocean was subducted northwards below the European and Adria Plates.
Oceanic spreading of the Alpine trough began in the Middle Jurassic and, from the Late Cretaceous, this ocean was subducted south and eastwards below the Adria Plate. The European origin of the CPA indicates a possible existence of direct communication between those two oceans. In our interpretation this connection was related to a sinistral trasform fault that crossed the western part of the modern Mediterranean area from the Late Triassic.
5) The presumed existence of a Jurassic microcontinent (AlKaPeCa) is critically discussed and it appears inconsistent with stratigraphic data. In conclusion, CPA (and the whole AlKaPeCa) cannot be considered as Austroalpine Units or a microcontinent, but as a marginal part the European plate involved in the north-dipping subduction of the Ionian Ocean. This subduction produced a southvergent stacking of the various Calabrian units and began around 43 Ma below the CPA, long before the involvement of the Corsica continental margin in the east-dipping subduction of the Alpine Ocean (34 Ma).

The role of sediment grain-size, mineralogy, and beach morphology on plant communities of two Mediterranean coastal dune systems

Volume:133 (2014) f.2 Pages:271-281 DOI:10.3301/IJG.2014.09

Abstract

AbstractCoastal dune ecosystems are characterized by a strong relationship between abiotic and biotic factors. The aim of the study is to identify the abiotic factors that mostly affect distribution and composition of plant dune communities along the coast-to-inland gradient, focusing the attention on sediment grain-size parameters, mineralogy, and dune morphology. The research was carried out on two coastal dune systems belonging to protected areas in the Mediterranean Basin, specifically in Northern and Southern Tuscany (Italy). Grain-size analysis, X-ray powder diffraction, topographic surveys, and floristic data recording were carried out along 11 transects perpendicular to the shoreline; the portion of the beach investigated is comprised within the foreshore and the backdune area. The analyses revealed some differences between the two coastal dune systems in terms of sediment parameters, mineralogy, and dune topography. The differences are mainly ascribed to the physical characteristics of the sites where the surveys were carried out. These data were matched with those provided by the vegetation sampling and then statistically processed by means of methods such as the Canonical Correlation Analysis (CCA), which showed that the mean grain-size is the most important abiotic factor that influences the composition of these coastal plant communities. These results might be considered to improve and optimize management and conservation programs for these ecosystems, since nowadays artificial dune reconstruction is a practice frequently used as a form of coastal protection.

Morphological and palaeoenvironmental evolution of the Lagoon of Papas, outhwestern Greece, during the Holocene (*)

Volume:133 (2014) f.2 Pages:282-293 DOI:10.3301/IJG.2014.10

Abstract

AbstractGeomorphological, stratigraphic and palaeoecological surveys have been carried out along the coastland of the Lagoon of Papas (Kalogrìa) since 1994, with the aim of depicting its morphodynamic and palaeoenvironmental evolution during the Holocene, until the present. The coast was previously affected by tectonic activity which exerted a morphologic control, interacting with the Quaternary sealevel changes. These processes resulted in subsidence during the MIS 7, followed by the MIS 5 transgression with marine and lagoon sediment deposition. The subsequent regression caused the deposition of alluvial covers and fans, later dislocated by the differential uplift which formed a terrace and a coastal plain at its base, tilted towards the northwest. This plain was dissected and uplifted by recent tectonics which has developed a new terrace, separated from the former by a post-Tyrrhenian fault scarp. Particularly, during the Holocene the coastal plain was characterized by the deposition of alluvial sediments eroded from the southwestern hills, increase of fluvial meanders, westward deviation of watercourses, development of ponds, swamps and finally of a lagoon.
Multidisciplinary studies, including examination of historical cartography, bathymetric map, microfossil analysis and geomorphological surveys, have shed light on the gradual genesis of the lagoon.
The lagoon developed during the Holocene in a pre-existing wide bay, starting from a sequence of a few littoral spits elongated from southeast to northwest. Palaeoecological analysis confirmed the alternation of brackish to marine environments, through the recognition of different groups of microfossil assemblages. Morphological and sedimentological study of the lagoon bottom showed some hummocks and facies related to buried relict spit and overwash structures.
This morphodynamic evolution is analogous to that described for some Tyrrhenian and Adriatic lagoons from Italy, as well as for other Mediterranean lagoons.

AbstractThe Arabescato Orobico is a decorative stone and building material from the Bergamasc Alps, Italy. From the geological standpoint it belongs to the Calcare Rosso, latest Ladinian-Early Carnian in age, which is a peritidal tepee-rich limestone strongly modified by superimposed early diagenetic processes, outcropping in Lombardy Southern Alps. In the last twenty-five years four commercial varieties have been available on the market, namely Grigio, Grigio-Rosa, Rosa, and Rosso, whose working and abandoned quarries, are located around the extraction districts of Camerata Cornello, and San Giovanni Bianco in the median Brembana Valley. Until the 1970s of the last century some different historical types, namely Rosso Antico, Rosso Venato, and Venato Finissimo, where extracted around Ardesio, in the Seriana Valley, as well. This paper deals with the stratigraphic analysis based on detailed physical correlations of several marker horizons mainly recognized along abandoned and active quarries, and their carbonate facies analysis. Stratigraphic results permit to divide the Calcare Rosso unit in three lithozones (CR1, CR2, and CR3), with a very low angle onlapping geometry at the top of the Esino Limestone. Southward (basinward) the Calcare Rosso gradually passes to dominant grey peritidal carbonates poor in tepee
horizons corresponding to the lower Breno Fm.. The petrographic characterization of representative samples from Mecca and Cadei quarries, permits to distinguish peculiar textural and compositional features of the four contemporaneous commercial types. As concerns the Grigio we identify almost five different subtypes, respectively
denominated Grigio Laguna, composed of fossiliferous subintertidal grey to dark grey and black wackestone-packstones, Grigio Granulare, composed of inter-supratidal pisolitic grey grainstonerudstones, Nero Raggiato, very rich in “raggioni”, dark grey to black fibrous-radial early diagenetic calcite, Grigio Laminato composed of poorly to middle deformed antiformal structures, namely embryo to mature tepees, and, finally, Grigio Brecciato, a grey-colored diagenetic-pedogenetic breccia. Remaining types, ascribed to pinkishgrey, Grigio-Rosa, pinkish, Rosa, and reddish, Rosso, colored diagenetic supratidal facies, can be divided into laminated or brecciated subtypes. The former are composed of antiformal syndepositional to early diagenetic structures, i.e. embryo to mature tepees; the brecciated subtypes consist of more diagenetically modified senile tepees passing to breccias. These types present different amounts of sediment filling, including internal calcitic and dolomitic sediments, pisolites, terra-rossa paleosols and green/reddish clays, and early cementation, such as fibrous isopachous crust, “raggioni”, sparry calcite, of the primary and early diagenetic cavities. The stratigraphic organization, and the facies analysis of this carbonate succession, have been used to evaluate the areal and vertical distribution of the Arabescato Orobico commercial types; in this way the Calcare Rosso depositional model is also suitable for geological prospecting and quarrying activities.

SCG: A Computer Application for Single Clinopyroxene Geothermobarometry

Volume:133 (2014) f.2 Pages:315-322 DOI:10.3301/IJG.2014.01

Abstract

AbstractSCG stands for Single Clinopyroxene Geothermobarometry, a software application for clinopyroxene geothermobarometry introduced
here for the first time to the scientific community along with an explanatory note. SCG is a highly specialised and user-friendly
application. It compiles 16 well-established clinopyroxene geothermobarometry calibrations, including 10 geobarometer and 6 geothermometer equations, to estimate temperature and pressure of crystallisation of clinopyroxene in mafic igneous systems. SCG flexibility allows the selection and use of any pair of preferred geothermometer and geobarometer equations. Therefore, it provides 60 different combinations to calculate simultaneously Pressure and
Temperature. It works both in a graphical and analytical form.